Ruggedized fiber optic connectors and connection systems

ABSTRACT

Example fiber optic connector systems have rugged, robust designs that are environmentally sealed and that are relatively easy to install and uninstall in the field. Some connector systems can be configured in the field to be compatible with different styles of fiber optic adapters. Some connectors include a first seal (90) on a release sleeve; and a second seal (88) between the release sleeve and a connector body. Other connectors include a seal (139) and a flexible latch (136) on a connector. Other connectors include a protective structure (228, 328, 428) that mounts over the fiber optic connector. Other connectors include a protective outer shell (528, 860) and a sealing and attachment insert (570, 570A, 876). Other connectors include a protective outer shell (728) and a fastener (780).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. patent application Ser. No.14/914,117, filed on Feb. 24, 2016, now U.S. Pat. No. 9,733,436, whichis a National Stage of PCT/EP2014/068010, filed Aug. 25, 2014, whichclaims the benefit of U.S. Provisional Application No. 61/869,672, filedon Aug. 24, 2013, U.S. Provisional Application No. 61/971,967, filed onMar. 28, 2014, and U.S. Provisional Application No. 61/973,677, filed onApr. 1, 2014, the disclosures of which are hereby incorporated herein byreference in their entireties. To the extent appropriate, a claim ofpriority is made to each of the above disclosed applications.

TECHNICAL FIELD

The present disclosure relates generally to fiber optic connectors. Moreparticularly, the present disclosure relates to fiber optic connectorssuitable for outside environmental use.

BACKGROUND

Fiber optic communication systems are becoming prevalent in part becauseservice providers want to deliver high bandwidth communicationcapabilities (e.g., data and voice) to customers. Fiber opticcommunication systems employ a network of fiber optic cables to transmitlarge volumes of data and voice signals over relatively long distances.Optical fiber connectors are an important part of most fiber opticcommunication systems. Fiber optic connectors allow two optical fibersto be quickly optically connected without requiring a splice. Fiberoptic connectors can be used to optically interconnect two lengths ofoptical fiber. Fiber optic connectors can also be used to interconnectlengths of optical fiber to passive and active equipment.

A typical fiber optic connector includes a ferrule assembly supported ata distal end of a connector housing. A spring is used to bias theferrule assembly in a distal direction relative to the connectorhousing. The ferrule functions to support an end portion of at least oneoptical fiber (in the case of a multi-fiber ferrule, the ends ofmultiple fibers are supported). The ferrule has a distal end face atwhich a polished end of the optical fiber is located. When two fiberoptic connectors are interconnected, the distal end faces of theferrules abut one another and the ferrules are forced proximallyrelative to their respective connector housings against the bias oftheir respective springs. With the fiber optic connectors connected,their respective optical fibers are coaxially aligned such that the endfaces of the optical fibers directly oppose one another. In this way, anoptical signal can be transmitted from optical fiber to optical fiberthrough the aligned end faces of the optical fibers. For many fiberoptic connector styles, alignment between two fiber optic connectors isprovided through the use of an intermediate fiber optic adapter.

Ruggedized (i.e., hardened) fiber optic connection systems include fiberoptic connectors and fiber optic adapters suitable for outsideenvironmental use. These types of systems are typically environmentallysealed and include robust fastening arrangements suitable forwithstanding relatively large pull loading and side loading. Exampleruggedized fiber optic connection systems are disclosed by U.S. Pat.Nos. 7,467,896; 7,744,288 and 8,556,520.

SUMMARY

Certain aspects of the present disclosure relate to a fiber opticconnector system that efficiently provides effective compatibility witha number of different types of ruggedized fiber optic adapterconfigurations. In certain examples, the fiber optic connector systemincludes an elongate connector core including a front end defining aplug portion and a rear end defining a cable anchoring location. Thefiber optic connector system also includes a first ruggedized exteriorassembly configured to be mounted over the elongate connector core. Thefirst ruggedized exterior assembly includes a first shroud configured tobe mounted in a sealed relation over the elongate connector core. Thefirst shroud has a forward end that includes a first keying arrangementfor rotationally keying the first shroud relative to a first ruggedizedfiber optic adapter. The first ruggedized exterior assembly alsoincludes a first ruggedized fastening element for securing the firstruggedized exterior assembly to the first ruggedized fiber opticadapter. The fiber optic connector system also includes a secondruggedized exterior assembly configured to be mounted over the elongateconnector core. The second ruggedized exterior assembly includes asecond shroud configured to be mounted in sealed relation over theelongate connector core. The second shroud has a forward end thatincludes a second keying arrangement for rotationally keying the shroudrelative to a second ruggedized fiber optic adapter. The first keyingarrangement has a different keying configuration than the second keyingarrangement. The second ruggedized exterior assembly also includes asecond ruggedized fastening element for securing the second ruggedizedexterior assembly to the second ruggedized fiber optic adapter. Thefirst ruggedized fastening element has a different fasteningconfiguration than the second ruggedized fastening element. The firstruggedized exterior assembly is usable in combination with the elongatedconnector core to make the fiber optic connector system compatible withthe first ruggedized fiber optic adapter and the second ruggedizedexterior assembly is usable in combination with the elongated connectorcore to make the system compatible with the second ruggedized fiberoptic adapter. In this way, the elongate connector core can be factorymounted to a cable, and the cable assembly can be shipped in the fieldwithout any ruggedized exterior assemblies mounted thereon. In thefield, a technician can install either the first ruggedized exteriorassembly or the second ruggedized exterior assembly on the elongateconnector core depending upon the style of ruggedized fiber opticadapter encountered. In this way, the system effectively providescompatibility with different styles of ruggedized fiber optic adapters.In other examples, the most commonly used style of ruggedized exteriorassembly can be factory mounted on the elongate connector core andshipped to the field. In this example, in the event a non-compatiblefiber optic adapter is encountered, the pre-installed ruggedizedexterior assembly can readily be removed and replaced with a ruggedizedexterior assembly that is compatible with the encountered ruggedizedfiber optic adapter.

Aspects of the disclosure are directed to a fiber optic connectorincluding a connector body having a distal end at least partiallyforming a plug portion of the fiber optic connector; a release sleevemounted on the connector body and movable relative to the connector bodyalong a lengthwise axis of the connector body; a first seal that extendsaround an exterior of the release sleeve; and a second seal that extendsaround an exterior of the connector body and provides sealing betweenthe release sleeve and the connector body.

Other aspects of the disclosure are directed to a fiber optic connectorincluding a connector body defining a plug portion at a distal end, aproximal portion at the proximal end, and an intermediate portionbetween the plug portion and the proximal portion; a seal that mountsaround the intermediate portion; and a flexible latch integrally formedwith the proximal portion.

Other aspects of the disclosure are directed to a fiber optic connectionarrangement including structure defining a port, the structure includingan exterior sleeve; a fiber optic adapter mounted at the port; a fiberoptic connector configured to be received within a receptacle of thefiber optic adapter; and a protective structure that mounts over thefiber optic connector. The fiber optic connector includes a connectorbody defining a plug portion and a boot attached the connector body. Theprotective structure includes a distal end that attaches to the exteriorsleeve of the port and a proximal end through which a cable connected tothe fiber optic connector is routed.

Other aspects of the disclosure are directed to a fiber optic connectionarrangement including a core connector assembly; a protective outershell; and a port fastener. The core connector assembly includes asealing and cable attachment unit and a connector body coupled to thesealing and cable attachment unit. The sealing and cable attachment unitincludes a seal. The protective outer shell is configured to couple tothe sealing and cable attachment unit of the core connector assembly.The protective outer shell engages the seal when the protective outershell is coupled to the core connector assembly. The port fastener isconfigured to couple the protective outer shroud to a port.

A variety of additional inventive aspects will be set forth in thedescription that follows. The inventive aspects can relate to individualfeatures and to combinations of features. It is to be understood thatboth the forgoing general description and the following detaileddescription are exemplary and explanatory only and are not restrictiveof the broad inventive concepts upon which the embodiments disclosedherein are based.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a fiber optic connector in accordancewith the principles of the present disclosure;

FIG. 2 is a perspective view of a release sleeve of the fiber opticconnector of FIG. 1;

FIG. 3 is a perspective view of a connector body of the fiber opticconnector of FIG. 1;

FIG. 4 is a cross-sectional view of a fiber optic adapter configured toreceive the fiber optic connector of FIG. 1;

FIG. 5 is a perspective view showing the fiber optic connector of FIG. 1inserted within a port of a closure, panel or other structure;

FIG. 6 is a cross-sectional view showing the fiber optic connector ofFIG. 1 mounted within the port of FIG. 5;

FIG. 7 is a perspective view of another fiber optic connector inaccordance with the principles of the present disclosure;

FIG. 8 show the fiber optic connector of FIG. 7 mounted within a port ofa closure, panel or other structure;

FIG. 9 is a perspective view of another connector arrangement inaccordance with the principles of the present disclosure;

FIG. 10 shows the connector arrangement of FIG. 9 secured at a port of aclosure, panel or other structure;

FIG. 11 is a cross-sectional view showing the connector and portarrangement of FIG. 10;

FIG. 12 illustrates a further connector arrangement in accordance withthe principles of the present disclosure;

FIG. 13 shows the connector arrangement of FIG. 12 with a connector ofthe connector arrangement inserted within a port of a closure, panel orother structure;

FIG. 14 is a cross-sectional view of the connector arrangement of FIG.12 secured at the port of FIG. 13;

FIG. 15 illustrates yet another connector arrangement in accordance withthe principles of the present disclosure;

FIG. 16 shows the connector arrangement of FIG. 15 secured at a port ofa closure, panel or other structure;

FIG. 17 is a cross-sectional view of the port and connector arrangementof FIG. 16;

FIGS. 18-20 show another connector arrangement 520 in accordance withthe principles of the present disclosure;

FIGS. 21-23 illustrate another connector arrangement 720 in accordancewith the principles of the present disclosure.

FIG. 24 illustrates another fiber optic connection system 720 inaccordance with the principles of the present disclosure;

FIGS. 25-27 illustrate how an example protective shell can be movablealong the fiber optic cable to provide access to the fiber opticconnector;

FIGS. 28-31 show another fiber optic connection system in accordancewith the principles of the present disclosure;

FIG. 32 shows an alternative embodiment where a stop is provided thatprevents the first fiber optic connector from being extended from theport and ensures that the first fiber optic connector remains seatedagainst the spring;

FIG. 33 illustrates a customizable fiber optic connector systemincluding an elongate connector core in accordance with the principlesof the present disclosure;

FIG. 34 illustrates the customizable fiber optic connector system ofFIG. 33 with a first ruggedized exterior assembly secured on theelongate connector core;

FIG. 35 shows the connector arrangement of FIG. 34 in perspective viewwith an outer fastening element removed for clarity;

FIG. 36 shows the customizable fiber optic connector system of FIG. 33with a second ruggedized exterior assembly secured on the elongateconnector core; and

FIG. 37 is a perspective view of the connector arrangement of FIG. 36with an outer fastening element removed for clarity.

DETAILED DESCRIPTION

The expansion of fiber optic networks toward the premises has driven thedemand for enhanced fiber optic connectors suitable for outsideenvironmental uses. For example, in a given fiber optic network, outsidefiber optic connectors are used to connect fiber optic cables tostructures such as drop terminals (i.e., multi-service terminals),optical network terminals (ONTs), breakout locations on fiber opticcables, fiber distribution hubs, splice closures, pedestals, or otherstructures. Effective use of fiber optic connectors in outsideenvironments requires the fiber optic connectors to be sealed againstthe environment and to have robust designs that can withstand relativelylarge temperature variations, large pulling loads, and significant sideloading. It is also desirable for such connectors to be relatively easyto insert and remove from a port in a structure of the type describedabove. The present disclosure describes various connectors havingrugged, robust designs that are environmentally sealed and that arerelatively easy to install and uninstall in the field.

FIG. 1 shows a fiber optic connector 20 in accordance with theprinciples of the present disclosure. Generally, the fiber opticconnector 20 includes a connector body 22 (see FIG. 3) having a lengththat extends along a lengthwise axis 24. The fiber optic connector 20also includes a release sleeve 26 (see FIG. 2) that mounts over theconnector body 22 and has a limited range of slidable movement relativeto the connector body 22 along the lengthwise axis 24.

Referring to FIG. 3, the connector body 22 includes a distal end 28 anda proximal end 30. A boot 32 is mounted adjacent the proximal end 30 ofthe connector body 22. The boot 32 is adapted to receive and providestrain relief to a fiber optic cable 34 to which the fiber opticconnector 20 is secured. The fiber optic cable 34 includes an opticalfiber 36 that is routed through the connector body 22. An end of theoptical fiber 36 is supported within a ferrule 38 accessible at thedistal end 28 of the connector body 22. The ferrule 38 can be springbiased in a distal direction relative to the connector body 22 by aspring 40.

As described above, the distal end 28 of the connector body 22 defines aplug portion of the fiber optic connector 20. The plug portion isadapted to be received within a fiber optic adapter 42 of the type shownat FIG. 4. The fiber optic adapter 42 includes first and secondreceptacles 44, 46 adapted to receive two fiber optic connectors desiredto be optically coupled together. The fiber optic adapter 42 includes analignment sleeve 48 for receiving and coaxially aligning the ferrules ofthe two fiber optic connectors desired to be coupled together. The fiberoptic adapter 42 also includes latches 50 corresponding to each of thereceptacles 46, 48. The latches 50 are adapted to mechanically retainthe fiber optic connectors within the receptacles 46, 48.

Referring back to FIG. 3, the connector body 22 includes exteriorshoulders 52 on opposite sides of the connector body 22. When the plugportion of the connector body 22 is inserted within the first receptacle44 of the fiber optic adapter 42, the ferrule 38 fits within thealignment sleeve 48 of the fiber optic adapter 42 and the latches 50snap past and latch against the exterior shoulders 52 to prevent theconnector body 22 from being removed from the first receptacle 44. Therelease sleeve 26 mounts over the connector body 22 and is provided fordisengaging the latches 50 from the exterior shoulders 52 when it isdesired to remove the fiber optic connector 20 from the first receptacle44. For example, as shown at FIG. 2, the release sleeve 26 includes rampsurfaces 54 configured to engage the latches 50. By pulling the releasesleeve 26 proximally relative to the connector body 22 when the fiberoptic connector 20 is mounted within the first receptacle 44, the rampsurfaces 54 of the release sleeve 26 are caused to engage the latches 50and to push the latches 50 outwardly away from the exterior shoulders 52of the connector body 22. Pushing the latches 50 away from the exteriorshoulders 52 effectively releases the fiber optic connector 20 from thelatches 50, thereby allowing the fiber optic connector 20 to bewithdrawn from the first receptacle 44.

Referring to FIG. 2, the release sleeve 26 includes a distal portion 56configured to fit within the first receptacle 44 of the fiber opticadapter 42. The ramp surfaces 54 are provided at opposite sides of thedistal portion 56. A distal key 58 fits within a corresponding slotprovided at the first receptacle 44. The release sleeve 26 also includesa proximal portion 60 that extends proximally away from the distalportion 56. The proximal portion 60 forms an elongated handle thatextends proximally beyond the proximal end 30 of the connector body 22.In one example, the proximal portion 60 is generally cylindrical andincludes a smaller diameter portion 62 separated from a larger diameterportion 64 by a radial step 66. The larger diameter portion 64 includesa proximal gripping portion 68. The release sleeve 26 also includes aproximal key 70 that is axially aligned with the distal key 58 and thatextends in a distal direction from the radial step 66.

Referring to FIG. 5, the fiber optic connector 20 is configured to beinserted within a port 80 defined by a structure 82 such as a terminal,a closure, an enclosure, a panel, a housing or other telecommunicationscomponent. In certain examples, the structure 82 is an environmentallysealed closure. While not depicted in FIGS. 5 and 6, a fiber opticadapter such as the fiber optic adapter 42 can be mounted at an interiorend 84 of the port 80 and can be configured for receiving the plug endof the fiber optic connector 20 when the fiber optic connector 20 isinserted within the port 80. FIGS. 5 and 6 show the fiber opticconnector 20 fully inserted within the port 80. The port 80 includes anexterior notch 86 at an exterior end 88 of the port 80. The exteriornotch 86 is adapted for receiving the proximal key 70 when the fiberoptic connector 20 is fully inserted within the port 80. In this way,the notch 86 and the key 70 ensure that the fiber optic connector 20 isinserted into the port 80 at the appropriate rotational orientation.

Referring to FIG. 6, the fiber optic connector 20 includes a sealingarrangement for preventing the intrusion of moisture or other materialinto the structure 82 when the fiber optic connector 20 is insertedwithin the port 80. In one example, the sealing arrangement includes anouter circumferential seal 88 (e.g., an O-ring seal) mounted in acircumferential groove defined within the exterior surface of thesmaller diameter portion 62 of the proximal portion 60 of the releasesleeve 26. It will be appreciated that the port 80 and the smallerdiameter portion 62 are both generally cylindrical in shape so as tofacilitate providing an effective seal with an O-ring type seal. Stillreferring to FIG. 6, the sealing arrangement also includes a seal 90between the release sleeve 26 and the connector body 22. The seal 90 isdefined between an inner surface of the release sleeve 26 and an outersurface of the connector body 22. In an example, the seal 90 is anO-ring seal shown mounted within a circumferential groove defined withina cylindrical portion of the connector body 22 located adjacent to theproximal end 30 of the connector body 22. The seal 90 engages an innersurface of the smaller diameter portion 62 of the release sleeve 26. Theouter portion of the connector body 22 and the inner surface of therelease sleeve 26 are generally cylindrical adjacent the seal 90 so asto enhance effective sealing with an O-ring type seal.

In use of the fiber optic connector 20, the fiber optic connector 20 isinserted into the port 80 such that the distal end of the fiber opticconnector is received within the first receptacle 44 of a fiber opticadapter secured at the interior end 84 of the port 80. When the fiberoptic connector 20 is inserted within the port 80, the latches 50 of thefiber optic adapter 40 engage the exterior shoulders 52 to secure theoptic connector 20 within the port 80. To remove the fiber opticconnector 20 from the port 80, the release sleeve 26 is grasped at thelarger diameter portion 64 and pulled in a proximal direction. As therelease sleeve 26 is pulled in a proximal direction relative to theconnector body 22, the ramp surfaces 54 push the latches 50 out ofengagement with the exterior shoulders 52 thereby allowing the fiberoptic connector 20 to be withdrawn from the port 80.

FIGS. 7 and 8 show another fiber optic connector 120 in accordance withthe principles of the present disclosure. Similar to the previousexample, the fiber optic connector 120 is adapted to be received withina fiber optic adapter 42 secured at the interior end of a port 180defined by a structure of the type previously described. The fiber opticconnector 120 includes a connector body 122 having a distal end 124 anda proximal end 126. The distal end 124 forms a plug end of the fiberoptic connector 120. A ferrule 129 supporting an optical fiber of afiber optic cable is accessible at the plug end of the fiber opticconnector 120. Ramped notches 128 are provided at opposite sides of theconnector body 122 adjacent the distal end 124. When the plug end of thefiber optic connector 120 is inserted within the fiber optic adapter 42,the latches 50 snap within the notches 128 to provide for lightretention of the fiber optic connector 120 within the port 180. Theconfiguration of the ramped notches 128 allows the connector body 122 tobe pulled from the latches 50 without the need of a release sleeve.

As described above, the connector body 122 includes a plug portion 130at the distal end 124. The ramped notches 128 are provided at oppositesides of the plug portion 130 and the ferrule is accessible at thedistal-most end of the plug portion 130. The connector body 122 alsoincludes an intermediate section 132 positioned at a proximal end of theplug portion 130. A radial shoulder 133 is defined between the plugportion 130 and the intermediate portion 132. The intermediate portion132 is generally cylindrical in shape and defines a circumferentialgroove in which a sealing member, such as an O-ring 135, is mounted. Theconnector body 122 also includes a proximal portion 134 positionedadjacent to the proximal end 126. The proximal portion 134 has agenerally rectangular transverse cross-sectional shape. The connectorbody 122 also includes a resilient latch 136 having a base end 138integrally formed with the proximal portion 134.

Referring to FIG. 8, the fiber optic connector 120 further includes aninner hub 144 that supports a spring 146 used to bias the ferrule in adistal direction. The hub 144 mounts within the connector body 122. Arear extension 148 can attach to the hub 144 and extend proximally fromthe proximal end 126 of the connector body 122. A boot or heat shrink150 can be mounted at the proximal end of the rear extension 148. Aswith the previous example, a fiber optic cable can be connected to thefiber optic connector 120 with a fiber of the fiber optic cable beingsupported at the ferrule. The heat shrink or boot 150 can be used toprovide strain relief at the interface between the cable and the fiberoptic connector 120 and can also provide sealing about the rearextension 148. In certain embodiments, a seal can also be providedbetween the exterior of the rear extension 148 and the interior of theconnector body 122.

Referring again to FIG. 8, the fiber optic connector 120 can be insertedinto the port such that the plug portion 130 is received within thereceptacle 44 of the fiber optic adapter 42. As so positioned, thelatches 50 of the fiber optic adapter 42 fit within the ramped notches128. Additionally, the latch 136 snaps within a catch 152 defined by theport 180. The port 180 includes a generally rectangular portion 156 thatreceives the intermediate portion 132 of the connector body 122 and acylindrical portion 158 that receives the proximal portion 134 of theconnector body 122. The intermediate portion 132 can define acircumferential groove in which an O-ring seal 139 is positioned. TheO-ring seal 139 can provide a seal between the connector body 122 andthe cylindrical portion of the port 180. To withdraw the fiber opticconnector 120 from the port 180, the latch 136 is depressed, therebydisengaging the latch 136 from the catch 152, thereby allowing the fiberoptic connector 120 to be axially pulled from the port 180.

FIGS. 9-11 show a connector arrangement 220 in accordance with theprinciples of the present disclosure. The connector arrangement 220includes a fiber optic connector 222, a port 224 defined within aclosure 226 or other structure, a fiber optic adapter 42 mounted at theport 224 and configured for receiving the fiber optic connector 222, anda protective shell 228 that mounts over the port 224 and encloses thefiber optic connector 224. Referring to FIG. 11, the fiber opticconnector 222 is depicted as an SC-type fiber optic connector. The fiberoptic connector 222 includes a connector body 230 having shoulders 232for engaging the latches 50 of the fiber optic adapter 42. The fiberoptic connector 222 mounts at the end of a fiber optic cable 235. Aflexible strain-relief boot 234 provides strain relief at the interfacebetween the fiber optic cable 235 and the connector body 230. An opticalfiber of the fiber optic cable 235 is supported within a ferrule 236accessible at the distal end of the fiber optic connector 222. A releasesleeve 238 mounts over the connector body 230. The release sleeve 238 isaxially moved relative to the connector body and includes rampstructures for disengaging the latches 50 from the shoulders of theconnector body 230 when it is desired to remove the fiber opticconnector 222 from the fiber optic adapter 42.

The port 224 includes an opening 250 in which the fiber optic adapter 42is mounted. The port 224 also includes an exterior sleeve 252 that isgenerally cylindrical and that surrounds the outer receptacle of theadapter 42. In the depicted embodiment, the sleeve 252 includes externalthreads 254.

The protective shell 228 is configured for ruggedizing, protecting, andsealing the connector-to-adapter interface at the port 224. Theprotective shell includes a distal end 260 and a proximal end 262. Theprotective shell 228 also includes an interior cavity 264 sized toreceive the fiber optic connector 220 therein. The distal end 260 isopen and substantially cylindrical.

In one example, the protective shell 228 can have a relatively rigidconstruction made of a hard, plastic material such as polymide or othermaterials. The distal end 260 can include internal threads that matewith the exterior threads 254 of the sleeve 252. A seal (e.g., an O-ringseal) can also be provided at the distal end 260 adjacent the threads.The proximal end 262 can support a sealing plug 270 that provides a sealbetween the jacket of the fiber optic cable 235 and the protective shell228. By threading the protective shell 228 onto the sleeve 252, thefiber optic connector 222 and the fiber optic adapter 42 are effectivelyprotected from the environment.

Referring to FIGS. 12-14, a further connector arrangement 320 isdepicted. The connector arrangement 320 has the same generalconfiguration as the connector arrangement 220 except the connectorarrangement 320 has a modified release sleeve 352 with a proximal flange353 and also has a modified protective shell 328 having an internalretention member 329 (FIG. 14). When the protective shell 328 isthreaded onto the sleeve 352, the retention member 329 abuts against theend flange 353 of the release sleeve 352 to provide additional retentionforce for retaining the fiber optic connector 322 within the port 224.

FIGS. 15-17 show still another connector arrangement 420 in accordancewith the principles of the present disclosure. The connector arrangement420 has the same basic configuration as the connector arrangement 220except the protective shell 228 has been replaced with a protective boot428. The protective boot 428 can have a flexible, bendable constructionsimilar to a standard boot on a fiber optic connector. The protectiveboot 428 includes an internal cavity configured for receiving the fiberoptic connector 222. A distal end of the protective boot 428 connects toa port structure 424 via a snap-fit connection. A proximal end of theprotective boot 428 can have a segmented, tapered configuration thatreduces in cross-sectional shape as the tapered structure extends in aproximal direction. The boot of the fiber optic connector can fit atleast partially within the tapered portion of the protective boot 428.

FIGS. 18-23 and 28 illustrate convertible connector arrangements thatenable different ruggedization features to be added to a core connectorassembly to fit with the particular interface provided at a given port.In each of the convertible connector arrangements, a connector body 530,830 is mounted to a sealing and cable attachment unit 570, 570A, 876,which can also be referred to as a universal connector mount. Theconnector body 530, 830 and sealing and cable attachment unit 570, 570A,876 together form the core connector assembly. As will be shown, variousshrouds 528, 860 and port fasteners 553, 870 can be added to the coreconnector assembly to enable the core connector assembly to fit atvarious ports 524, 824. In some example cases, various fasteners 602,884 couple the shrouds 528, 860 to the sealing and cable attachmentunits 570, 876. In other example cases, the shroud 528 fastens directlyto the sealing and cable attachment unit 570A (e.g., by a snap-fitconnection).

As shown in FIG. 19, a ferrule assembly 531 and a fiber guide 534 aremounted within the connector body 530. (The corresponding features alsoare visible in FIG. 28.) The ferrule assembly 531 includes a ferrule 533mounted to a hub 535. The ferrule 533 includes a central passage 537 forreceiving an optical fiber. The ferrule assembly 531 further includes aspring 532 for biasing the hub 535 and the ferrule 533 in a forwarddirection relative to the connector body 530. A front of the fiber guide534 forms a spring stop against which one end the spring 532 seats. Theother end of the spring 532 abuts against a flange on the hub 535 tobias the hub 535 forward relative to the fiber guide 534. The hub 535 isheld between the spring 532 and the connector body 530.

The connector body 530, 830 includes a front end 539 and a rear end 541.The ferrule assembly 531 mounts within the connector body 530 adjacentthe front end 539. As so mounted, the ferrule 533 is accessible at thefront end 539 of the connector body 530. The front end 539 of theconnector body 530, 830 forms a plug configured to be received within acorresponding fiber optic adapter 542. The sealing and cable attachmentunit 570, 570A, 876 extends through the rear end 541 of the connectorbody 530, 830 and engages the fiber guide 534. In certain examples, theconnector body 530, 830 can have a form factor consistent with anSC-connector. However, other types of connector bodies can be utilized.For example, as shown at FIG. 31, the fiber optic connectors 530, 830can have modified shoulders that are angled or tapered so as to beremovable from the fiber optic adapter 842 without the use of a releasesleeve. Thus, in the depicted example of FIG. 31, the fiber opticconnector 828 does not have a release sleeve.

FIGS. 18-20 show a connector arrangement 520 in accordance with theprinciples of the present disclosure. The connector arrangement 520includes a fiber optic connector 522 having a connector body 530 and asealing and cable attachment unit 570. As shown at FIG. 20, the fiberoptic adapter 542 can include an alignment sleeve 543 configured forreceiving the ferrule 533. In certain examples, the fiber optic adapter542 can be mounted at a port 524 within a closure 526 or otherstructure. In the depicted example, the fiber optic adapter 542 does nothave latches at the port 524 for engaging the connector body 530.Additionally, the connector arrangement 520 does not include a releasesleeve that mounts over the connector body 530.

Referring still to FIGS. 18-20, the connector arrangement 520 furtherincludes an example protective shroud or shell 528 that mounts over theconnector body 530. The protective shell 528 mounts to the sealing andcable attachment unit 570 of the connector 522. The protective shell 528can include a front end 545 and a rear end 547. The front end 545 caninclude a key or keying arrangement for providing rotational alignmentbetween the protective shell 528 and the port 524. In certain examples,an environmental seal can be provided between the protective shell 528and the closure 526 to provide sealing of the port 524. While thesealing can be provided in a variety of ways, in the depicted example,sealing can be provided by a seal 549 (e.g., an O-ring seal) that mountsabout an exterior of the protective shell 528 near the front end 545. Inthe depicted example, the seal 549 is a radial seal mounted within acircumferential groove 551 defined at the exterior of the protectiveshell 528. When the protective shell 528 is inserted within the port 524of the closure 526, the seal 549 is radially compressed between theexterior surface of the protective shell 528 and a circumferentialsealing surface defined by the closure 526 at the port 524. In otherexamples, axial seals, face seals, or other types of seals can be used.Moreover, in still other examples, the protective shell 528 can fit overa sleeve provided at the port 524 and sealing can be provided betweenthe interior of the protective shell and the exterior of the sleeve.

In certain examples, a retaining element or fastener can be used tosecure the protective shell 528 within the port 524. In one example, theretaining element can include fastening structures such as threads orbayonet members that interlock with the corresponding fasteningstructures provided at the port 524. In the depicted embodiment, aretaining structure in the form of a fastening nut 553 is used to retainthe protective shell 528 within the port 524. The fastening nut 553includes external threads 555 that mate with corresponding internalthreads 557 of the port 524 to retain the protective shell 528 withinthe port 524. The fastening nut 553 includes an engagement portion 559(e.g., a front end) that engages a corresponding engagement portion 561(i.e., a shoulder) of the protective shell 528 so as to retain theprotective shell 528 within the port 524 (see FIG. 20). The fasteningnut 553 is positioned over the protective shell 528 and is free torotate about a central axis of the protective shell 528 and is also freeto move axially relative to the protective shell 528.

As indicated above, the fiber optic connector 522 mounts within theprotective shell 528. The connector assembly 520 further includes asealing and cable attachment unit 570 positioned at the rear end 547 ofthe connector body 530. In one example, the sealing and cable attachmentunit 570 attaches at the rear end 541 of the connector body 530. Forexample, the sealing end cable attachment unit 570 can attach to therear end 541 of the connector body 530 by a mechanical interface such asa snap-fit connection, a threaded connection, a bayonet type connectionor other type of connection. As depicted, the sealing end cableattachment unit 570 is secured to the connector body 530 by a snap-fitconnection. In one example, the sealing and cable attachment unit 570 iscoupled to the connector body 530 by inserting the sealing and cableattachment unit 570 through the rear end 547 of the shell 528 andattaching the sealing and cable attachment unit 570 to the rear end 541of the connector body 530.

In certain examples, a fiber optic cable 580 can be secured to thesealing and cable attachment unit 570. An optical fiber 582 of the fiberoptic cable can extend through the sealing and cable attachment unit 570through the connector body 530 to the ferrule 533. In certain examples,adhesive can be used to secure the optical fiber 582 within the ferrule533. The fiber optic cable 580 can also include an outer jacket 584 anda strength element (e.g., a reinforcing component such as Aramid yarn,fiber reinforce epoxy rods, fiberglass strands, etc.). In certainexamples, the jacket 584 and the reinforcing structure can be secured tothe sealing and cable attachment unit 570. For example, the jacketand/or the reinforcing structure can be crimped, mechanically bonded orotherwise attached to the sealing and cable attachment unit 570. Incertain examples, a structure such as a heat shrink sleeve can be usedto provide sealing between the jacket 584 and the sealing and cableattachment unit 570.

The sealing and cable attachment unit 570 includes a rear body 590defining a central passage 592 for receiving the optical fiber 582. Incertain examples, the rear body 590, protective shell 528 and theconnector body 530 can all have a relatively rigid construction made ofa hard, plastic material such as polymide or other materials. The rearbody 590 includes attachment structure for securing the sealing andcable attachment unit 570 to the rear end 541 of the connector body 530.For example, the rear body 590 includes snap-fit tabs 594 that fitwithin corresponding openings 595 defined by the connector body 530. Incertain examples, environmental sealing is provided between the rearbody 590 and the protective shell 528. For example, the rear body 590can fit within the protective shell 528 and a seal can be providedtherein between. In certain examples, the seal can include a radial sealthat provides sealing between an exterior circumferential surface of therear body 590 and an interior circumferential surface of the protectiveshell 528. In other examples, an axial seal may be used to providesealing against an axial end of the protective shell 528. In thedepicted example, the sealing and cable attachment unit 570 includes aradial seal 596 (e.g., an O-ring seal) that is radially compressedbetween an exterior surface of the rear body 590 and an interior surfaceof the protective shell 528. In the depicted example, the seal 596mounts within a circumferential groove 598 defined about the peripheryof the rear body 590. The sealing and cable attachment unit 570 furtherincludes a rear pocket 599 for receiving the jacket 584 of the fiberoptic cable 580. The rear pocket 599 is defined by a rear extension 600of the rear body 590. In certain examples, a heat shrink sleeve can beapplied over the rear extension and over the jacket so as to providesealing between the rear body 590 and the exterior of the cable jacket584.

In certain examples, the connector arrangement 520 can include afastener 602 that connects the shroud 528 to the sealing and cableattachment unit 570. In the depicted example, the fastener 602 in theform of an internally threaded sleeve 602 having internal threads thatmate with corresponding external threads provided at the rear end 547 ofthe protective shell 528. In certain examples, the fastener 602 isstructured for enhancing sealing of the sealing and cable attachmentunit 570 within the protective shell 528. For example, the fastener 602can act as a radial compression element. When mounted at the rear end547 of the protective shell 528, the fastener 602 can radially compressthe protective shell 528. By radially compressing the rear end 547 ofthe protective shell 528, the seal 596 is radially compressed andfriction between the protective shell 528 and the sealing and cableattachment unit 570 is enhanced so as to resist the sealing and cableattachment unit 570 from being withdrawn rearwardly from the protectiveshell 528. In certain examples, the fastener 602 and the protectiveshell 528 can have mating tapers that generate or enhance radialcompression of the protective shell 528 as the fastener is threaded onthe rear end of the protective shell 528.

The connector arrangement 520 further includes a strain relief boot 604that mounts to the rear end 547 of the protective shell 528 and thatcoincides with a portion of the fiber optic cable 580. The strain reliefboot 604 can have a flexible configuration and can be configured toprovide strain relief and bend radius protection to the fiber opticcable 580 at the interface between the fiber optic cable and theconnector arrangement 520.

In certain examples, one or more seals for sealing the port 524 can beprovided between the fastening element and the closure 526.

In certain examples, the connector arrangement 520 can also include adust cap 606 that mounts over the front end 539 of the fiber opticconnector 522 and over the front end 545 of the protective shell 528when the connector arrangement 520 is not in use. The dust cap 606 caninclude internal threads 608 that mate with the threads of the fasteningelement. When it is desired to use the connector arrangement 520, thedust cap is removed thereby allowing the connector arrangement 520 to beinserted into the port 524. When the connector arrangement 520 isinserted into the port 524, the front end 539 of the fiber opticconnector 522 is received within the fiber optic adapter 542 and theferrule 533 is received within the alignment sleeve 543 of the fiberoptic adapter 542. Also, the front end 545 of the protective sleeve 528fits within the port 524 and can be rotationally aligned by intermatingkeying structures such as projections, tabs, paddles, etc. With theprotective shell 528 inserted within the port 524, the seal 549 forms aseal between the exterior of the protective shell 528 and the portion ofthe closure 526 defining the port 524. With the fiber optic connector522 and the protective sleeve 528 inserted within the port 524, thefastening nut 553 can be slid forwardly along the protective shell 528until the external threads 555 engage the internal threads 557 of theport 524. The fastening nut 553 is then threaded into the port 524.Engagement between the engagement portions 559, 561 retains theconnector arrangement 520 within the port 524.

FIGS. 21-23 illustrate another connector arrangement 520A in accordancewith the principles of the present disclosure. The connector arrangement520A has the same basic arrangement as the connector arrangement 520 ofFIGS. 18-20, except a modified sealing and cable attachment unit 570A isprovided. The sealing and cable attachment unit 570A has the same basicconstruction as the sealing and cable attachment unit 570, except thesealing and cable attachment unit 570A is configured to interconnectwith the rear end of the protective shell 528 by a snap-fit connection.For example, snap-fit tabs are snapped within corresponding openingsdefined by the protective shell 528 such that the sealing and cableattachment unit 570A is effectively attached to the protective shell528. In one example, a front portion of the sealing and cable attachmentunit 570A is inserted through the rear end 547 of the shell 528 and anintermediate portion of the sealing and cable attachment unit 570Aattaches to the rear end 547 of the shell 528.

FIG. 24 illustrates another fiber optic connection system 720 inaccordance with the principles of the present disclosure. The fiberoptic connection system 720 includes a closure 726 (e.g., a housing,enclosure, box, etc.) defining a port 724. The fiber optic connectionsystem 720 also includes a first fiber optic cable 725 positioned insidethe closure 726 and a second fiber optic cable 727 positioned outsidethe closure 726. In certain examples, first fiber optic cable 725 isless robust than the second fiber optic cable 727. The first and secondfiber optic cables 725, 727 have connectorized ends that are opticallyconnected at the port 724.

Referring still to FIG. 24, a receptacle 750 forming an adapter mount isconnected (integrally or mechanically connected) to an inner surface ofthe closure 726 in general alignment with the port 724. A fiber opticadapter 742 is mounted within the receptacle 750. While a variety ofdifferent styles of fiber optic adapters can be used, one example, thefiber optic adapter 742 is an SC-type fiber optic adapter adapted forreceiving an SC-type fiber optic connector.

The fiber optic adapter 742 includes first and second oppositereceptacles 741, 743. The fiber optic adapter 742 also includes analignment sleeve 745. The first fiber optic cable 725 is terminated by afiber optic connector 760 that is received in the first receptacle 741and the second fiber optic cable 727 is terminated by a fiber opticconnector 762 that is received within the receptacle 743. When receivedwithin their respective receptacles 741, 743, ferrules of the fiberoptic connectors 760, 762 are coaxially aligned such that an opticalconnection is made between the optical fibers of the first and secondoptical cables 725, 727. In the depicted example, fiber optic connectors760, 762 are SC-type connectors configured to latch within the first andsecond receptacles 741, 743. The fiber optic connectors 760, 762 includerelease sleeves that can be retracted to unlatch the fiber opticconnectors 760, 762 from their respective receptacles 741, 743.

The fiber optic connection system 720 further includes a protectiveshell 728 that is secured to the closure 726 at the port 724 and thatprotects the fiber optic connector 762. In certain examples, protectiveshell 728 can have a fastening element for fastening the protectiveshell 728 to the closure 726 at the port 724. Sample fasteningstructures can include mating threads provided at the port 724 and theprotective shell 728, mating bayonet connection elements providedbetween the protective shell 728 and the closure 726, snap-fitconnections between the protective shell 728 and the closure 726, orother structures. As depicted, the protective shell includes a front end763 having external threads 765 that mate with corresponding internalthreads 767 defined within the port 724 (e.g., within the receptacle750). In certain examples, environmental sealing is also providedbetween the closure 726 and the protective shell 728 at the port 724. Asdepicted, a seal 767 (e.g., an O-ring seal) is positioned around theprotective shell 728 adjacent the front end 763. As depicted, the seal767 is a face seal that is axially compressed between a flange 769 ofthe protective shell 728 and a sealing surface 771 of the closure 726when the protective shell 728 is secured at the port 724.

Referring still to FIG. 24, the protective shell 728 further includes amain body 773 and a rear extension 775. The rear extension 775 has asmaller diameter than the main body 773 and projects rearwardly from themain body 773. The rear extension 775 defines a rear end 777 of theprotective shell 728. The second fiber optic cable 727 extends throughthe rear end 777 of the protective shell 728 and extends through themain body 773 to the fiber optic connector 762 received within the fiberoptic adapter 742. A seal 778 is used to provide a circumferential sealabout the jacket of the fiber optic cable 727 and to provide sealing atthe rear end 777 of the protective shell 728. In one example, the seal778 can include an O-ring seal that extends around the outer diameter ofthe fiber optic cable 727. The fiber optic connection system 720 furtherincludes a seal pressurization/deformation member 780. In one example,seal pressurization/deformation member 780 that is connected to the rearextension 775 and used to axially compress the seal 778 such that theseal radially deforms about the fiber optic cable 727 and effectivelyseals the opening defined through the rear extension 775. In oneexample, the seal pressurization member 780 is threaded on the rearextension 775.

The fiber optic connection system 720 further includes a boot 782carried with the seal pressurization member 780 for providing strainrelief and bend radius protection to the fiber optic cable 727 adjacentthe rear end of the fiber optic connection system 720.

Referring to FIG. 25, the protective shell 728 is movable along thefiber optic cable 727 to provide access to the fiber optic connector762. For example, to access the fiber optic connector 762 when the fiberoptic connector 762 is coupled to the port 724, the seal pressurizationmember 780 is initially loosened to decompress the seal 778. Next, theprotective shell 728 is decoupled (e.g., unthreaded) from the port 724and retracted rearwardly from the port 724 by sliding the protectiveshell 728 along the fiber optic cable 727 (see FIG. 25). Once theprotective shell 728 has been retracted as shown at FIG. 25, the releasesleeve of the fiber optic connector 762 can be manually grasped andretracted so as to disengage the fiber optic connector 762 from itscorresponding receptacle 743 in the fiber optic adapter 742.

To secure and seal the fiber optic connector 762 at the port 724, thefiber optic connector 762 is initially inserted within the receptacle743 of the fiber optic adapter 742. Next, the protective shell 728 isslid over the fiber optic connector 762 and threaded into the port 720as shown at FIG. 26. With the protective shell 728 threaded within theport 724, the seal 767 is compressed to provide effective sealing aroundthe port 724 and the front end 763 of the protective shell 728. Once theprotective shell 728 has been secured within the port 724, the sealpressurization member 780 is threaded onto the rear extension 775 of theprotective shell 728 thereby causing the seal 778 to be deformed to asealing state in which the rear end 777 of the protective shell 728 issealed so as to prevent moisture from intruding through the rearextension 775. FIG. 27 shows the seal pressurization member 780 in asealing position.

FIGS. 28-31 show another fiber optic connection system 820 in accordancewith the principles of the present disclosure. The fiber opticconnection system 820 includes a closure 822 defining a port 824. Thefiber optic connection system 820 further includes a first fiber opticcable 825 terminated by a first fiber optic connector 826 and a secondfiber optic cable 827 terminated by a second fiber optic connector 828.The fiber optic connection system 820 further includes a fiber opticadapter 842 for optically coupling the first and second fiber opticconnectors 826, 827 together such that an optical transmission path isdefined between the first and second fiber optic cables 825, 827. Incertain examples, the fiber optic connectors 826, 828 can have a formfactor consistent with an SC-connector. However, as shown at FIG. 31,the fiber optic connectors 826, 828 can have modified shoulders that areangled or tapered so as to be removable from the fiber optic adapter 842without the use of a release sleeve. Thus, depicted example, the fiberoptic connector 828 does not have a release sleeve.

The fiber optic connection system 820 includes a receptacle 850 throughwhich the fiber optic cable 825 extends. A spring 851 or other biasingstructure is provided within the receptacle 850. When the fiber opticconnection system 820 is assembled and connected together, the spring851 engages the fiber optic connector 826 to provide resilience supportthat allows the fiber optic connector to float within the receptacle850.

In other examples, the outer port of the fiber optic adapter 842 may beconfigured to not include any latches thereby eliminating the need for arelease sleeve on the second fiber optic connector 828.

The fiber optic connection system 820 further includes a protectiveouter shell or shroud 860 having a front end 862 and an opposite rearend 864. The shroud 860 extends over the connector body 830. A sealingelement 866 is positioned about the protective shell 860 adjacent thefront end 862. In certain examples, the sealing element 866 can buttagainst a radial shoulder 868 that projects outwardly from a main bodyof the protective outer shell 860. When the protective outer shell 860is secured within the port 824, the sealing element 866 is axiallycompressed to provide an effective seal between the protective outershell 860 and the closure 822.

The fiber optic connection system 820 further includes a port fastener870 for securing the protective outer shell 860 within the port 824. Inone example, the port fastener 870 is a retention nut having externalthreads that mate with corresponding internal threads defined within theport 824. As shown at FIG. 28, the port fastener 870 can abut againstthe radial shoulder 868 to effectively retain the protective outer shell860 within the port 824. In alternative embodiments, the port fastener870 can include other types of retention structures such as snap-fitstructures, ratchet structures, bayonet-type fittings or other types ofstructures for effectively securing the port fastener 870 to the closure822. It will be appreciated that the port fastener 870 can be rotatedrelative to the protective outer shell 860 so as to allow the portfastener 870 to be threaded into the port 824 without rotating theprotective outer shell 860.

The protective outer shell 860 includes a main body and a rear extension872. A sealing element 874 is provided adjacent the rear extension forsealing the rear end 864 of the protective outer shell 860. The sealingelement 874 is mounted about sealing and cable attachment unit 876having a forward end 877 that fits within the rear extension 872 of theshroud 860. The sealing element 874 is captured between the rear end 864of the protective outer shroud 860 and a radial flange 878 of thesealing and cable attachment unit 876. The sealing and cable attachmentunit 876 also includes a rear pocket 880 in which a jacket of the secondfiber optic cable 827 can be secured. In certain examples, a cable seal,such as a shape-memory (e.g., heat shrink) sealing sleeve, can besecured over the jacket and over the rear of the rear insert so as toeffectively seal the fiber optic cable 827 relative to the sealing andcable attachment unit 876.

The fiber optic connection system 820 further includes a sealcompression element 884 that attaches to the rear extension 872 of theprotective outer shroud 860 and that functions to axially compress thesealing element 874. In one example, fastening elements such as threadscan be provided between the seal compression element 884 and the rearextension 872. By threading the seal compression element 884 on the rearextension 872, the sealing and cable attachment unit 876 is forcedaxially toward the rear end 864 of the rear extension 872, therebycausing the sealing element 874 to be compressed between the rear end864 and the radial flange 878. When compressed, the sealing element 874effectively seals the rear end of the protective outer shell 860.

In certain examples, the first fiber optic connector 826 can be extendedand retracted relative to the port 824. For example, the first fiberoptic cable 825 can include a stop positioned a length L from the fiberoptic connector 826. This allows the connector to be pulled thepredetermined length L from the port 824 to provide access for cleaningor making connections. FIG. 29 shows the fiber optic connector 826 inthe extended position, while FIG. 28 shows the fiber optic connector inthe retracted position. In the retracted position of FIG. 28, the fiberoptic connector 826 seats against the spring 851.

FIG. 29 shows the port 824 prior to making a connection between thefirst and second fiber optic cables 825, 827. As shown at FIG. 29, theport 824 is closed and sealed by a dust cap 890 that is threaded intothe port 824 and that includes a port seal 892. As shown at FIG. 29, thefiber optic adapter 842 is absent from the port 824.

To make an optical connection between the first and second fiber opticcables 825, 827, the dust cap 890 is removed and the fiber optic adapter842 is installed on the first fiber optic connector 826. Next, thesecond fiber optic connector 828 is inserted into the fiber opticadapter 842 such that an optical connection is made between the firstand second fiber optic cables 825, 827. Next, the connector assembly isretracted back into the port 824 until the first fiber optic connector826 abuts against the spring 851. Subsequently, the protective outershell 860 is inserted over the connector assembly and inserted into theport 824 until the sealing element 866 is compressed between the radialshoulder 868 and a corresponding sealing surface of the port 824. Theattachment element 870 is then threaded into the port 824, therebylocking the protective outer shell 860 within the port 824 andcompressing the sealing element 866. Finally, the seal compressionelement 884 is threaded onto the rear extension 872 over the protectiveouter shell 860 to effectively compress the sealing element 874. Unlikethe previous example system, it is not necessary to decompress thesealing element 874 to remove the second fiber optic connector 828 fromthe fiber optic adapter 842. Instead, to disconnect the second fiberoptic connector 828 from the fiber optic adapter 842, the attachmentelement 870 is disconnected from the port 870 and the protective outershell 860 is withdrawn from the port 824. As the protective outer shell860 is withdrawn from the port 824, the second fiber optic connector 828moves with the protective outer shell 860 and disengages from the fiberoptic adapter 842. Unlike the previous example, the second fiber opticconnector 828 does not include a release sleeve that is required to beaccessed to disengage the fiber optic connector 828 from the fiber opticadapter 842.

As shown at FIG. 29, prior to use of the port 824, the fiber opticadapter 842 is not installed on the fiber optic connector 825. Incertain examples, this can assist in differing costs. However, in otherexamples, the fiber optic adapter 842 can be installed on the firstfiber optic connector 825 and stored within the dust cap prior toconnection with the second fiber optic cable 827. In still furtherexamples, the fiber optic adapter 842 can be integrated with the secondfiber optic connector 828 (e.g., be installed on the second fiber opticconnector 828 within the protective outer shell 860). In this example,the fiber optic adapter 842 and the second fiber optic connector 828 areinserted together into the port 824 along with the protective outershell 860 during the connection process. Insertion continues until thefirst fiber optic connector 825 snaps into the fiber optic adapter 842and subsequently abuts against the spring 851.

As described above, in the fiber optic connection system 820, the firstfiber optic connector 826 can be extended and retracted relative to theport 824 by pulling the first fiber optic cable 825 outwardly from theclosure 822 through the port 824, and by pushing the fiber optic cable825 back into the closure 822 through the port 824. As indicated above,a stop can be provided on the first fiber optic cable 825 for limitingthe length of the first fiber optic cable 825 that can be extended fromthe port 824. FIG. 32 shows an alternative embodiment where a stop isprovided that prevents the first fiber optic connector 826 from beingextended from the port 824 and ensures that the first fiber opticconnector 826 remains seated against the spring 851.

FIGS. 33-37 illustrate a ruggedized, customizable fiber optic connectorsystem 900 in accordance with the principles of the present disclosure.The fiber optic connector system 900 includes an elongate connector core902. The fiber optic connector system 900 also includes first and secondruggedized exterior assemblies 904, 906 that can be mounted over theelongate connector core 902 to customize the fiber optic connectorsystem 900. For example, a user may choose whether to mount the firstruggedized exterior assembly 904 or the second ruggedized exteriorassembly 906 over the elongate connector core 902.

The first and second ruggedized exterior assemblies 904, 906 havedifferent configurations from one another. For example, the firstruggedized exterior assembly 904 has a configuration that is compatiblewith a first ruggedized fiber optic adapter 908 while the secondruggedized exterior assembly 906 has a configuration that is compatiblewith a second ruggedized fiber optic adapter 910. The first and secondruggedized fiber optic adapters 908, 910 have different fastening andkeying configurations and, therefore, are typically compatible withdifferent styles of fiber optic connectors.

By selecting either the first ruggedized exterior assembly 904 or thesecond ruggedized exterior assembly 906 and mounting the selectedruggedized exterior assembly on the elongate connector core 902, thefiber optic connector system 900 can be readily customized in the fieldso as to be compatible with the particular style of fiber optic adapterthat may be encountered in the field. In this way, the elongateconnector core 902 functions as a precursor structure that can readilybe made compatible with different styles of ruggedized fiber opticadapters by selecting the appropriate ruggedized exterior assembly andmounting the selected ruggedized exterior assembly on the elongateconnector core 902.

Referring to FIG. 33, the elongate connector core 902 includes a frontend 912 and an opposite rear end 914. In certain examples, the elongateconnector core 902 can include a core housing 916 that extends from thefront end 912 to the rear end 914. It will be appreciated that the corehousing 916 can include one or more pieces.

The front end 912 of the elongate connector core 902 defines a plugportion configured to be received within a fiber optic adapter. Incertain examples, the plug portion can have a form factor that matchesan existing conventional connector style such as a form factorcorresponding to an SC connector, an LC connector, or other type offiber optic connector. In one example, the plug portion can have a formfactor consistent with a DLX connector of the type disclosed in U.S.Pat. No. 7,467,896, the disclosure of which is hereby incorporatedherein by reference in its entirety.

Still referring to FIG. 33, the rear end 914 of the elongate connectorcore 902 defines a cable anchoring location for securing a fiber opticcable 918 to the elongate connector core 902. It will be appreciatedthat the fiber optic cable 918 can include an outer jacket 920surrounding an optical fiber 922. The fiber optic cable 918 can alsoinclude strength members (e.g., tensile strength members such as Aramidyarns, fiber reinforced epoxy rods, etc.) that are secured to the cableanchoring location of the elongate connector core 902. In certainexamples, the strength members can be secured using conventionaltechniques such as crimping or adhesive.

It will be appreciated that the fiber optic cable 918 can also be sealedrelative to the elongate connector core 902. For example, as shown atFIG. 34, a shape-memory sleeve 924 (e.g., a heat shrink sleeve) is showncovering the interface between the rear end 914 of the elongateconnector core 902 and the fiber optic cable 918. In certain examples,the shape-memory sleeve 924 can be adhesively bonded to the elongateconnector core 902 and the outer surface of the outer jacket 920. Thus,the shape-memory sleeve 924 can function to mechanically anchor thefiber optic cable 918 to the elongate connector core 902 while alsoproviding a seal between the elongate connector core 902 and the fiberoptic cable 918.

In certain examples, optical access to the optical fiber 922 can beprovided at the plug portion defined by the front end 912 of theelongate connector core 902. For example, a ferrule 926 can be providedat the front end 912 of the elongate connector core 902. The opticalfiber 922 can be coupled to the ferrule 926. For example, the opticalfiber 922 can be directly potted within a central bore of the ferrule926. Alternatively, the optical fiber 922 can be spliced to a stub fiberpotted within the bore of the ferrule 926. In either alternative, theoptical fiber 922 is considered optically coupled to the ferrule 926. Incertain examples, the ferrule 926 can be spring biased in a forwarddirection toward the front end 912 of the elongate connector core 902.

In certain examples, the elongate connector core 902 is tunable. Bytunable, it is meant that the rotational orientation of the ferrule 926about its central longitudinal axis can be adjusted relative to the corehousing 916 to position a core offset (i.e., an eccentricity) of theoptical fiber within the ferrule 926 at a desired rotational position.Examples of tuning are disclosed at U.S. Pat. No. 5,212,752 and PCTInternational Publication No. WO 02/052310, the disclosures of which arehereby incorporated herein by reference in their entirety. It will beappreciated that tuning of the elongate connector core 902 can takeplace during assembly of the elongate connector core 902. During theassembly process, the core offset of the optical fiber within theferrule 926 can be rotated to a particular rotational orientationrelative to a key structure corresponding to the core housing 916. Oncetuned, the rotational position of the ferrule 926 can be retainedrelative to the core housing 916 by an interface between a ferrule hubof the ferrule 926 and the core housing 916 or by other types ofretention arrangements provided within the core housing 916. In certainexamples, keyed relationships also exist between the elongate connectorcore 902 and shrouds of the ruggedized exterior assemblies 904, 906 suchthat the shrouds can only be mounted to the core 902 in onepredetermined rotational orientation.

As shown at FIG. 33, the elongate core 902 can include a seal 928configured for providing an annular seal between the core housing 916and the first ruggedized exterior assembly 904 or between the corehousing 916 and the second ruggedized exterior assembly 906. In oneexample, the seal 928 is an O-ring mounted within an annular groovedefined by the core housing 916. In certain examples, the seal 928 isnot configured to engage with a corresponding ruggedized adapter. Thus,in certain examples, the sole function of the seal 928 is to providesealing with a ruggedized exterior assembly used to customize theelongate connector core 902 to a particular adapter style. In thedepicted example, the seal 928 is positioned rearward of a longitudinalmidpoint 930 of the elongate connector core 902. Such a rearwardpositioning of the seal 928 prevents the seal 928 from being used toprovide an annular seal within the port of a corresponding fiber opticadapter.

The fiber optic connector system 900 further includes a fastener thatmounts on the elongate connector core 902 and that is suitable forattaching either the first ruggedized connector assembly 904 or thesecond ruggedized exterior assembly 906 to the elongate connector core902. In certain examples, the fastener can be a threaded member such asa nut, a bayonet-type fitting, a snap-fit structure, or other structure.In the depicted embodiment, the fastener includes a fastening structure932 incorporated into a strain-relief boot 934 that mounts at the rearend 914 of the elongate connector core 902. The strain-relief boot 934is configured to provide strain relief to the fiber optic cable 918 atthe interface between the rear end 914 of the elongate connector core902 and the fiber optic cable 918. In certain examples, a strain-reliefboot 934 can have a resilient, polymeric construction. In the depictedexample, the rear strain-relief boot 934 includes a tapered rear end 935having an exterior surface that tapers inwardly as the strain-reliefboot 934 extends in a rearward direction. The tapered rear end 935 caninclude circumferential slits or slots that function to segment thetapered rear end 935 of the strain-relief boot 934 so as to enhance theflexibility. The fastening structure 932 is depicted as internal threads936 provided within the strain-relief boot 934 adjacent a front end ofthe strain-relief boot 934. In certain examples, the front end of thestrain-relief boot 934 can have a construction that is more rigid ormore robust than the rear end of the strain-relief boot. In certainexamples, the fastening structure 932 can be embedded or otherwiseintegrated into the strain-relief boot 934. In other examples, thefastening structure 932 can be a unitary feature molded or otherwiseformed into the strain-relief boot 934.

Referring again to FIG. 33, the first ruggedized exterior assembly 904is configured to be mounted over the elongate connector core 902 andincludes a first shroud 938 configured to be mounted in sealed relationover the elongate connector core 902. For example, as shown at FIG. 34,when the first shroud 938 is installed over the elongate connector core902, a rear end of the first shroud 938 abuts against an annularshoulder 940 of the elongate connector core 902 and the seal 928provides an annular radial seal circumferentially between the exteriorcircumference of the elongate connector core 902 and the innercircumference of the first shroud 938. The first shroud 938 has aforward end that includes a first keying arrangement 942 forrotationally keying the first shroud 938 relative to the firstruggedized fiber optic adapter 908. As depicted, the first keyingarrangement 942 includes a pair of paddles 944 (see FIG. 35) configuredto be received within corresponding recesses (not shown) defined withinthe port of the first ruggedized fiber optic adapter 908. The firstruggedized exterior assembly 904 also includes a first ruggedizedfastening element 946 (omitted from FIG. 35) for securing the firstruggedized exterior assembly 904 to the first ruggedized fiber opticadapter 908. In one example, the first ruggedized fastening element 946includes a coupling nut having external threads 948 that mate withcorresponding internal threads 950 of the first ruggedized fiber opticadapter 908 to secure the elongate connector core 902 and the firstruggedized exterior assembly 904 within the first ruggedized fiber opticadapter 908.

As shown at FIG. 34, the first fiber optic adapter 908 includes analignment sleeve 952 that receives the ferrule 926. Additionally, thefirst ruggedized exterior assembly 904 includes an exterior seal 953that provides a circumferential radial seal between the first shroud 938and the inner surface of the first ruggedized fiber optic adapter 908.Referring to FIG. 34, the rear end of the first shroud 938 includes afastening feature 954 (e.g., external threads) that couples with thefastening structure 932 to secure the first shroud 938 to the elongateconnector core 902.

In other examples, the first ruggedized fastening element 946 can havealternative configurations. For example, in alternative configurations,the first ruggedized fastening element can include a sleeve havinginternal threads that mate with corresponding external threads of acorresponding fiber optic adapter. In certain examples, the firstruggedized fastening element 946 is a twist-to-lock fastening element.In other examples, snap-fit or other types of interlocking mechanismsalso can be used. In certain examples, the fastening structure 932 canbe referred to as a shroud retainer. In certain examples, the shroudretainer is not configured to engage with a corresponding ruggedizedfiber optic adapter. In certain examples, the sole function of theshroud retainer is to retain a selected ruggedized exterior assembly tothe elongate connector core 902.

Referring back to FIG. 33, the second ruggedized exterior assembly 906is configured to be mounted over the elongate connector core 902 andincludes a second shroud 960 configured to be mounted in sealed relationover the elongate connector core 902. When the second shroud 960 ismounted over the elongate connector core 902, a rear end of the secondshroud 960 abuts against the annular shoulder 940 of the elongateconnector core 902 and a fastening feature 962 (e.g., external threads)engage with the fastening structure 932 to axially retain the secondshroud 960 on the elongate connector core 902. Additionally, as shown atFIG. 36, the seal 928 forms a radial, circumferential seal between theelongate connector core 902 and an internal surface of the second shroud960.

The second shroud 960 has a forward end including a second keyingarrangement 964 for rotationally keying the second shroud 960 relativeto the second ruggedized fiber optic adapter 910. For example, thesecond keying arrangement 964 can include an open ended slot 966 definedat the forward end of the second shroud 960. When exterior assembly 906is installed on the elongate connector core 902 and inserted into theport of the second ruggedized fiber optic adapter 910, the open endedslot 966 receives a corresponding projection 968 provided within thesecond ruggedized fiber optic adapter 910 so as to provide rotationalkeying of the second shroud 960 and the second ruggedized fiber opticadapter 910. As so inserted, the ferrule 926 of the elongate connectorcore 902 is received within an alignment sleeve 967 of the secondruggedized fiber optic adapter 910 and an exterior seal 970 providedaround the second shroud 960 provides a radial, circumferential sealbetween an outer surface of the second shroud 960 and an inner surfaceof the second ruggedized fiber optic adapter 910.

The second ruggedized exterior assembly 906 also includes a secondruggedized fastening element 972 for securing the second ruggedizedexterior assembly 906 with the elongate connector core 902 securedthereto to the second ruggedized adapter 910. In the depicted example,the second ruggedized fastening element 972 includes a sleeve having abayonet-style connection configuration. For example, the sleeve caninclude internal bayonet pins 973 that fit within corresponding bayonetslots 975 defined in a collar of the second ruggedized fiber opticadapter 910. FIG. 36 shows the bayonet-style sleeve interlocked with thecollar of the second ruggedized fiber optic adapter 910.

As described above, the first ruggedized exterior assembly 904 is usablein combination with the elongated connector core 902 to make the fiberoptic connector system compatible with the first ruggedized adapter 908and the second ruggedized exterior assembly 906 is usable in combinationwith the elongated connector core 902 to make the system compatible withthe second ruggedized fiber optic adapter 910. In certain examples, thefirst and second ruggedized exterior assemblies 904, 906 are installedon the elongate connector core 902 by inserting the first or secondshrouds 938, 960 in a front-to-rear direction over the front end 912 ofthe elongate connector core 902 and rearwardly onto the elongateconnector core 902. In certain examples, it will be appreciated that theconfiguration of the first ruggedized fastening element 946 is differentfrom the configuration of the second ruggedized fastening element 972.Additionally, it will be appreciated that the first keying arrangement942 has a configuration that is different from the second keyingarrangement 964.

In certain examples, the bayonet interface can be reversed such thatpins are provided on the collar of the second ruggedized fiber opticadapter 910 while bayonet slots are provided within the bayonet sleeve.Similar to the first ruggedized fastening element 946, it will beappreciated that other configurations can be utilized for the secondruggedized fastening element 972. Additionally, different keyingconfigurations also can be utilized. Thus, it should be appreciated thatthe keying configurations and the fastening configurations are providedfor example only, and other types of configurations can be used as well.

In certain examples, the elongate connector core 902 is a precursorstructure that is not intended to be mounted within a ruggedized fiberoptic adapter without the use of a corresponding ruggedized exteriorassembly. In other examples, the elongate connector core 902 can beconverted to be compatible with a ruggedized fiber optic adapter withoutrequiring the use of an intermediate shroud. For example, the plug endof the elongate connector core 902 can be provided with a DLX formfactor (e.g., as shown at FIG. 31) and the elongate connector core 902can be converted to a DLX-type connector by installing a fiber opticadapter seal over the exterior of the elongate connector core 902adjacent the front end and by installing a ruggedized fastening elementdirectly over the elongate connector core 902 without an intermediateshroud. In certain examples, the ruggedized fastening element can besecured to the elongate connector core 902 via the fastening structure932.

The above specification, examples and data provide a completedescription of the manufacture and use of the composition of theinvention. Since many embodiments of the invention can be made withoutdeparting from the spirit and scope of the invention, the inventionresides in the claims hereinafter appended.

LIST OF REFERENCE NUMERALS AND CORRESPONDING FEATURES

-   20 a fiber optic connector-   22 a connector body-   24 a lengthwise axis-   26 a release sleeve-   28 a distal end-   30 a proximal end-   32 a boot-   34 a fiber optic cable-   36 an optical fiber-   38 a ferrule-   40 a spring-   42 a fiber optic adapter-   44, 46 first and second receptacles-   48 an alignment sleeve-   50 latches-   52 exterior shoulders-   54 ramp surfaces-   56 distal portion-   58 distal key-   60 proximal portion-   62 a smaller diameter portion-   64 a larger diameter portion-   66 a radial step-   68 a proximal gripping portion-   70 proximal key-   80 port-   82 structure-   84 interior end-   86 exterior notch-   88 an outer circumferential seal-   90 seal-   120 another fiber optic connector-   122 connector body-   124 distal end-   126 proximal end-   128 ramped notches-   129 ferrule-   130 plug portion-   132 an intermediate section-   133 a radial shoulder-   134 a proximal portion-   135 sealing member-   136 a resilient latch-   138 base end-   139 O-ring seal-   144 inner hub-   146 spring-   148 rear extension-   150 heat shrink or boot-   152 catch-   180 port-   220 a connector arrangement-   222 a fiber optic connector-   224 port-   226 closure-   228 protective shell-   230 connector body-   232 shoulders-   234 strain relief boot-   235 fiber optic cable-   236 ferrule-   238 release sleeve-   250 opening-   252 exterior sleeve-   254 external threads-   260 a distal end-   262 a proximal end-   264 interior cavity-   270 a sealing plug-   320 a further connector arrangement-   322 fiber optic connector-   328 protective shell-   329 retention member-   352 modified release sleeve-   353 proximal flange-   420 connector arrangement-   424 port structure-   428 protective boot-   520 connector arrangement-   522 fiber optic connector-   524 port-   526 closure-   528 protective shell-   530 connector body-   531 ferrule assembly-   532 spring-   533 ferrule-   535 hub-   537 central passage-   539 front end-   541 rear end-   542 fiber optic adapter-   543 alignment sleeve-   545 front end-   547 rear end-   549 seal-   551 circumferential groove-   553 fastening nut-   555 external threads-   557 internal threads-   559, 561 engagement portions-   570 sealing and cable attachment unit-   570A modified sealing and cable attachment unit-   580 a fiber optic cable-   582 optical fiber-   584 jacket-   590 rear body-   592 central passage-   594 snap-fit tabs-   595 openings-   596 radial seal-   598 circumferential groove-   599 rear pocket-   600 a rear extension-   602 internally threaded sleeve-   604 strain relief boot-   606 dust cap-   608 internal threads-   720 connector arrangement-   724 port-   725 first fiber optic cable-   726 closure-   727 second fiber optic cable-   728 protective shell-   741 first receptacle-   742 fiber optic adapter-   743 second receptacle-   745 alignment sleeve-   750 receptacle-   760, 762 fiber optic connectors-   763 front end-   765 external threads-   767 internal threads-   769 flange-   771 sealing surface-   773 main body-   775 rear extension-   777 rear end-   778 seal-   780 a seal pressurization/deformation member-   782 boot-   820 fiber optic connection system-   822 closure-   824 port-   825 first fiber optic cable-   826 first fiber optic connector-   827 second fiber optic cable-   828 second fiber optic connector-   830 connector body-   842 fiber optic adapter-   850 receptacle-   851 spring-   860 outer shell-   862 front end-   864 rear end-   866 sealing element-   868 radial shoulder-   870 attachment element-   872 rear extension-   874 sealing element-   876 sealing and cable attachment unit-   877 forward end-   878 radial flange-   880 rear pocket-   884 seal compression element-   890 dust cap-   892 port seal-   900 fiber optic connector system-   902 elongate connector core-   904 first ruggedized exterior assembly-   906 second ruggedized exterior assembly-   908 first ruggedized fiber optic adapter-   910 second ruggedized fiber optic adapter-   912 front end-   914 rear end-   916 core housing-   918 fiber optic cable-   920 outer jacket-   922 optical fiber-   924 shape-memory sleeve-   926 ferrule-   928 seal-   930 longitudinal midpoint-   932 a fastening structure-   934 strain-relief boot-   935 tapered rear end-   936 internal threads-   938 first shroud-   940 annular shoulder-   942 first keying arrangement-   944 paddles-   946 first ruggedized fastening element-   948 external threads-   950 internal threads-   952 alignment sleeve-   953 exterior seal-   954 fastening feature-   960 second shroud-   962 fastening feature-   964 second keying arrangement-   966 open ended slot-   967 alignment sleeve-   968 projection-   970 exterior seal-   972 second ruggedized fastening element-   973 internal bayonet pins-   975 bayonet slots

What is claimed is:
 1. A fiber optic connection arrangement comprising:a connector arrangement having a front end and an opposite rear end, thefront end defining a plug end of the connector arrangement, theconnector arrangement including: a connector body terminating a fiber ofa fiber optic cable; and a protective outer shell disposed around theconnector body, the protective outer shell extending from a first end toa second end, the first end being open to provide access to theconnector body, the second end defining an aperture through which thefiber optic cable extends; and a sealing insert coupled at the rear endof the connector arrangement, the sealing insert being insertablethrough the aperture from the second end of the protective outer shell.2. The fiber optic connection arrangement of claim 1, wherein thesealing insert is coupled to a rear end of the connector body.
 3. Thefiber optic connection arrangement of claim 1, wherein the sealinginsert is coupled to a rear end of the protective outer shell.
 4. Thefiber optic connection arrangement of claim 1, wherein the sealinginsert includes an insert body and a seal disposed around an exterior ofthe insert body so that the seal is radially compressed between theinsert body and the protective outer shell when the sealing insert iscoupled to the rear end of the connector arrangement.
 5. The fiber opticconnection arrangement of claim 1, wherein the sealing insert issnap-fit to the rear end of the connector arrangement.
 6. The fiberoptic connection arrangement of claim 5, further comprising a threadedsleeve mounted to the protective outer shell to radially compress theprotective outer shell about the sealing insert.
 7. The fiber opticconnection arrangement of claim 1, further comprising a second sealdisposed at a front of the protective outer shell.
 8. The fiber opticconnection arrangement of claim 1, further comprising a fastener mountedto the protective outer shell, the fastener being configured to mountthe fiber optic connection arrangement to a port.
 9. The fiber opticconnection arrangement of claim 8, wherein the fastener includes afastening nut having external threads.
 10. A fiber optic cablearrangement comprising: a connector body extending between a front endand a rear end, the front end defining a plug; a protective outer shelldisposed around the connector body, the protective outer shell extendingfrom a front end to a rear end, the front end being open to provideaccess to the connector body, the rear end defining an aperture throughwhich the fiber optic cable extends; and a sealing insert disposed atthe rear end of the connector body, the sealing insert being insertablethrough the aperture from the second end of the protective outer shell,the sealing insert defining a central passage; and a fiber optic cableterminated by the connector body, the fiber optic cable extendingthrough the central passage of the sealing insert, the fiber optic cablebeing secured to the sealing insert.
 11. The fiber optic cablearrangement of claim 10, wherein the sealing insert secures to the rearend of the connector body by a snap-fit connection.
 12. The fiber opticcable arrangement of claim 10, further comprising a retaining elementdisposed about the protective outer shell, the retaining elementincluding a fastening structure, the retaining element shaped to engagethe protective outer shell.
 13. The fiber optic cable arrangement ofclaim 12, wherein the fastening structure includes threads.
 14. Thefiber optic cable arrangement of claim 12, wherein the fasteningstructure includes a bayonet.
 15. The fiber optic cable arrangement ofclaim 10, wherein the protective outer shell is configured to mate witha port of a receiving structure, wherein an environmental seal isprovided between the protective outer shell and the receiving structure.16. The fiber optic cable arrangement of claim 15, wherein the front endof the protective outer shell includes a keying arrangement forproviding rotational alignment between the protective outer shell andthe port of the receiving structure.
 17. The fiber optic cablearrangement of claim 15, wherein the environmental seal is carried bythe protective outer shell.
 18. The fiber optic cable arrangement ofclaim 17, wherein the environmental seal includes a radial seal carriedin a circumferential groove defined at an exterior of the protectiveouter shell.
 19. The fiber optic cable arrangement of claim 15, whereinthe receiving structure includes a closure defining the port, wherein anadapter is disposed within the port defined by the closure, and whereinthe environmental seal is spaced from the adapter.
 20. A fiber opticconnection arrangement comprising: a connector body extending between afront end and a rear end, the connector body holding a ferrule toterminate an optical fiber cable, the rear end of the connector bodydefining a plurality of openings; a protective outer shell disposedaround the connector body, the protective outer shell extending from afront end to a rear end, the front end being open to provide access tothe connector body, the rear end defining an aperture through which thefiber optic cable extends, the protective outer shell carrying a firstradial seal; a sealing insert disposed at the rear end of the connectorbody, the sealing insert defining a central passage, the sealing insertalso including a plurality of snap-fit tabs that fit within the openingsof the connector body to hold the sealing insert at the connector body,the sealing insert also carrying a second radial seal that engages aninner surface of the protective outer shell, the sealing insert beingsufficiently small to fit through the rear end of the protective outershell; and a twist-to-lock fastener mounted around the protective outershell, the twist-to-lock fastener being axially moveable relative to theprotective outer shell along a limited axial range.
 21. The fiber opticconnection arrangement of claim 1, further comprising a boot coupled tothe rear end of the connector arrangement.